EP 1034451 A1 20000913 - FERROELECTRIC LIQUID CRYSTAL DEVICES WITH TWISTED STRUCTURE
Title (en)
FERROELECTRIC LIQUID CRYSTAL DEVICES WITH TWISTED STRUCTURE
Title (de)
FERROELEKTRISCHE FLÜSSIGKRISTALLVORRICHTUNG MIT VERDRILLTER STRUKTUR
Title (fr)
DISPOSITIFS A CRISTAUX LIQUIDES FERROELECTRIQUES A STRUCTURES TORSADEES
Publication
Application
Priority
- US 9825158 W 19981125
- US 98044797 A 19971128
Abstract (en)
[origin: WO9928778A1] A hybrid analog/binary electro-optic modulator using a twisted ferroelectric liquid crystal structure is provided. Ferroelectric liquid crystals with a tilt angle of between about 20 DEG and about 25 DEG , preferably about 22.5 DEG are used. Rubbing directions for the two cell walls (relative to one another) can be varied from about 45 DEG to about 90 DEG . In one embodiment, a weak buffing force is used resulting in a relatively weak anchoring energy at the surface, aligning the liquid crystal molecules without locking the molecules into the buffing directions and a high pre-tilt structure for the molecules close to the surface boundaries. In one embodiment, strong buffing is used with buffing directions offset about 45 DEG . Use of this invention provides relatively fast response time, low required driving voltage, high contrast, and/or the ability to achieve both analog and binary operations.
IPC 1-7
IPC 8 full level
C09K 19/02 (2006.01); G02F 1/137 (2006.01); G02F 1/141 (2006.01); G02F 1/31 (2006.01)
CPC (source: EP US)
C09K 19/0225 (2013.01 - EP US); G02F 1/141 (2013.01 - EP US); G02F 1/31 (2013.01 - EP US)
Citation (search report)
See references of WO 9928778A1
Designated contracting state (EPC)
DE FR GB IT NL
DOCDB simple family (publication)
WO 9928778 A1 19990610; AU 1702599 A 19990616; CA 2308199 A1 19990610; EP 1034451 A1 20000913; JP 2001525560 A 20011211; US 6141076 A 20001031
DOCDB simple family (application)
US 9825158 W 19981125; AU 1702599 A 19981125; CA 2308199 A 19981125; EP 98961785 A 19981125; JP 2000523579 A 19981125; US 98044797 A 19971128